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Raspberry Pi NOAA Weather Satellite Receiver

January 2nd, 2018, 09:08 AM

It was a few years ago that I configured my Windows desktop to download NOAA weather maps for testing purposes. I used an antenna (DIY'd) in the attic and an RG6 cable to the office PC. It worked but was a bit kludgy.

This experiment and radio can be used to receive wireless information from a variety of wireless sensors for use with Homeseer. I will post a DIY on how to do this. There is a plugin using LUA for the Domoticz open source automation program that already does this. You can read wireless electric meters, water meters et al. (Temperature sensors et al)

Someone wrote a DIY in 6 steps to configure a RPI to do this.

Tweaking base here using Apache2 and PHP to post sound files and images on the Wheezy website. Someone is doing this in South Africa.

Note the endeavor is being done via bash scripts / command line utilities. Last time I tried this used Windows SDR utilities.

Here my current RPi2 in the attic is running Wheezy and functions as a ZNet like device, one wire hub and test Domotiz server. I added the NOAA download map functions to it over the last few days.

Here is a list of Hardware pieces necessary.

Raspberry Pi 3 Model B or Raspberry Pi 2 $35.00 USD (Amazon)

MicroUSB Power Supply (option 1) $5.00 USD

POE power splitter $15.00 USD

Generic Raspberry Pi 3 Case $10.00 USD

16 or 32 GB Micro SD Card $10.00 USD

NooElec SDR Dongle (part of Ebay or Amazon Kit) $26.00

V-Dipole Antenna (part of Ebay or Amazon Kit)

Total guesstimate Price = $100.00

OPTIONAL

DIY'd Quadrifilar Helix (QFH) Antenna PVC = $10.00

Amplifier ~ $10.00 on Amazon

FM Filter ~ $16.00 on Amazon

SMA connectors - F-Type to SMA, SMA couplers

Note here with my testing using the current RPi2 running Wheezy in the attic via a POE connection. It is doing other stuff today:

Future testing may connect another SDR radio (have a spare) to do custom rf remote sensor captures as this is today a plugin for Domoticz already being tested and written in LUA or Python. What I am writing about is that you do not need to purchase another RPi if you already have one available for use.

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Step 1: Prepare the Raspberry Pi

he first step is getting the Raspberry Pi up and running. I’m using Wheezy

There are plenty of tutorials on getting Raspbian set up and booting on the Raspberry Pi. You should have no difficulty in finding one.

Once you have the Raspbian image copied to your micro SD card, boot the Raspberry Pi. You'll need to get it on the network and enable SSH. You can certainly use either a wired Ethernet connection, or wireless. I'm using wireless, as I don't have a wired connection in my attic.

Enable SSH using the Raspberry Pi Configuration utility in the Preferences menu. You may want to set it to boot to CLI while you are in there. Since this is going to be a headless setup, there is no need to waste resources on a GUI.

Next we want to make sure the Raspberry Pi is fully up-to-date. Issue the following commands:

sudo apt-get update
sudo apt-get upgrade
sudo reboot

Step 2: Install the Necessary Software

The first thing we need is the USB drivers for the RTL dongle:
sudo apt-get install libusb-1.0

Since we need to build the latest version of rtl-sdr to actually make use of the RTL dongle, we'll need to install cmake:
sudo apt-get install cmake

We need to make sure the Raspberry Pi doesn't load any SDR kernel modules that will interfere with the rtl-sdr sofware.

Using your favorite text editor, create a new file named /etc/modprobe.d/no-rtl.conf and put the following text in the file. You need to run that text editor as sudo (i.e. 'sudo vi' or 'sudo nano' etc) to write to the modprobe.d directory:

-2 seems like a good number and I used -1 for the P variable in a coming described script.

If you receive any error messages, you'll need to troubleshoot them before continuing. If your RTL Dongle isn't working at this point, it won't do any good to continue.

You need to run predict one time to set your ground station location. To do that you'll need your latitude and longitude. You can get your latitude and longitude from google maps by searching for your address, the right clicking on the pointer and selecting "What's Here". One thing to note is that Google displays North as positive and East as positive numbers. Predict uses North as positive but WEST as positive. Make sure to adjust accordingly, or your predictions will be no good.

Run predict from the command line, and select option 'G'. Enter your ground station information and exit the program.:

Note here that you DO NOT USE a negative value for your Station Longitude if you station is in the Midwest.

You need to run wxtoimg once to accept the terms and conditions.

wxtoimg

You need to tell wxtoimg where your base station is at, so it can properly generate an overlay map. You do so by creating a file in your home directory named ~/.wxtoimgrc. In this file, North is positive, as with predict, however EAST is positive, which is the opposite of what predict uses. Make sure to adjust your values appropriately.

Using your favorite text editor, create a new file named ~/.wxtoimgrc and put the following text in the file, substituting your values:

Latitude: 41.7169
Longitude: -72.7271
Altitude: 25

NOTE here you utilize a negative number for Longitude if you are in the midwest.

Step 4: The Scripts

Now that you've got a working RTL dongle on your Raspberry Pi, it's time to actually make it receive some weather maps. Make sure your antenna is connected and located as best as possible. I've got mine mounted in my attic and it works fairly well from there. If you can mount it outside, that would be even better. Get it as high as possible.

We are going to need to create a few scripts to automate everything. This is where that Linux familiarity is going to come in.

First we'll create a couple directories to hold our files:

cd ~
mkdir weather
cd weather
mkdir predict
cd predict

Next we'll make the two scripts that kick off the scheduling. The first is 'schedule_all.sh'. This script will be called nightly at midnight. It downloads satellite pass information from celestrak and creates a TLE file for predict to use. Then it removes all AT jobs from the system, so no passes get double scheduled. Finally, it calls the second script 'schedule_satellite.sh' for each satellite we are interested in.

Using your favorite text editor, create a new file in ~/weather/predict named schedule_all.sh and put the following code in the file:

The second script, 'schedule_satellite.sh', recurses through each pass of the given satellite for the current day. It determines if the maximum elevation is 20 degrees or greater. If it is, then it calculates the length of the pass, and schedules the recording and processing of the pass. If the maximum elevation is less than 20 degrees, the pass is ignored, as it generally won't produce a decent image.

Using your favorite text editor, create a new file in ~/weather/predict named schedule_satellite.sh and put the following code in the file:

When the time comes for a give pass to be recorded and processed, at kicks off the final script 'receive_and_process_satellite.sh'. When this script is called, it uses rtl_fm to receive the audio from the satellite pass, and sends that audio to sox for processing. Sox saves the audio to a file. Once the pass is complete, wxmap is called to generate an overlay map for the image. Finally, wxtoimg is called to generate the actual image and place the overlay map on it.

Using your favorite text editor, create a new file in ~/weather/predict named receive_and_process_satellite.sh and put the following code in the file:

ZA = NOAA general purpose meteorological IR enhancement option. Increases contrast by saturating the very low and very high temperature regions where there is typically very little information. This enhancement option is temperature normalised.

NO = NOAA colour IR contrast enhancement option. Greatly increases contrast in the darker land/sea regions and colours the cold cloud tops. Allows fine detail in land and sea to be seen and provides a very readable indication of cloud top temperatures. This enhancement option is temperature normalised.

MSA = Multispectral analysis. Uses a NOAA channel 2-4 image and determines which regions are most likely to be cloud, land, or sea based on an analysis of the two images. Produces a vivid false-coloured image as a result. This enhancement takes up to three options separated from the enhancement name by colons. The first option is the sea to land adjustment. The default value is 50 with the valid range being 0 to 100. This should be decreased if land appears blue, and increased if water appears green. The second option is the land to cloud adjustment. The
default value is 50 with the valid range being 0 to 100. This should be decreased if cloud appears green and increased if land appears gray or white. The final option should be 0 to indicate warm or summertime analysis or 1 to indicate there are large cold regions. Note that perfect colouring is difficult to obtain, especially with low illumination angles. This enhancement does not use a palette nor is it temperature normalised.

Once all three scripts have been created, we need to make the executable, by issuing the following commands:

The format of the file name is the satellite name, followed by the date (YYYYMMDD) and time (HHMMSS) of the start of the pass. There are several filters that wxtoimg can use when generating the image file. I've had different luck with different satellites and passes on each filter. Feel free to play around with wxtoimg on the original map and audio files and see what you come up with.

One thing to note, the receiver can only receive one satellite at a time. If two satellites are passing overhead at the same time, the first one to start recording will "win" and be recorded. The second recording will error out and stop.

Here is a first attempt. Need to adjust antenna and wave file conversion. Basically it works like a fax reception. The application takes the wave file and converts it to a picture.

1 - Moved the antenna a bit.
2 - edited the scripts a bit
3 - sound is good now but pictures are still lousy.

4th of January, 2018 0700C

1 - Two settings were adjusted in Bash script.
2 - changed PPM (PPM stands for parts per million) to zero (0) as default was set to 55 relating to error correction.
3 - adjusted gain a bit from default of 45 to 55.
4 - listening to wave sound captures noticing louder satellite signals captures and for a longer time.
5 - pictures are coming out better with less noise but not soup yet.

5th of January, 2018 0700C

Still the same here with about 2-3 minutes of a solid signal and a lot of noise.
I do see a large antenna tower to the southwest so adding:

1 - FM bypass filter made for SDR listed on Amazon for ~$10.00

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2 - SDR 30dB amplifier listed on Amazon for ~$10.00

[ATTACH]65671[/ATTACH]

These come with adapters for antenna. The amplifier can be powered from a 6VDC battery.

6th of January, 2018 0730C

1 - Redid compass readings and noticed differences between second floor and main floor of home. Using a digital electronic compass. Re-adjusted antenna angle, checked length and pointed it to South as seen by the electronic compass. Results are better now with better pictures.
2 - ordered amplifier as pictured above

Note: whole point of DIY is to utilize the above mentioned kit with small V shaped antenna in my attic. Only add now is amplifier which was $10.

7th of January, 2018 0730C

Slowly getting there. Here is a NOAA 19 picture from this morning. There is still much static to the image.

Thinking this relates to the pickyness of using the V-Dipole antenna which is highly directional and small (20" V) Starting the recordings at 30 degrees now. Tried at 10 degrees and got more noise.

Figure the arc of capture is using 180 degrees. The script configuration is currently at 30 degrees start. Going to change it to 40 degrees start and add amplifier and filter to see what happens. IE: current capture is around 10 minutes. Going to see about changing it to 8 minutes.

Another endeavor this week is to build a new small (2nd time) Quadrifilar Helix (QFH) Antenna using PVC, glue and RG6 coaxial cable. Cost should be less than $10 and the footprint is around 4 feet tall. My attic ceiling is around 8 foot so that means that I will climb a ladder in the attic to hang the antenna up high. It's omni directional but thinking the RF footprint will be the same as the directional V dipole but I will not need to adjust it. Here will try to be neat with my cuts and will use a template to drill the holes in to the 2" PVC tube. The use of drill templates will allow for the cross members to be 90 degrees from each other. Only need to solder on the top and solder on an antenna coupler on the bottom.

Note that I am doing this because I have installed the V-Dipole in the attic and it's a PITA to adjust it. My digital compass readings are different in the attic than the main floor of the house. I currently hear a good signal from the NOAA 19 satellite and a piss poor signal from NOAA 15 and NOAA 18. Thinking that the omni directional Quadrifilar Helix (QFH) will work better.

This article describes how to make a quadrifilar helix (QFH) antenna easily, from inexpensive materials: uPVC plumbing pipe and RG-58U co-axial cable. No bending and soldering of copper pipe is required. If you have been put off making one of these highly effective antennas because you thought it was difficult, that you needed to be a time-served plumber, or that the antenna won't work unless the design is reproduced to sub-millimetre accuracy, don't be. If I can make one of these antennas and it works, then you can too!

Although not obvious from the diagram, there are notches at the end of each support arm, to help locate and hold the co-ax. The notch at one end is made at 90 degrees to the notch at the other. When the supports are mounted in the mast, the notch facing you must be oriented so that it slopes at 45 degrees from top left to bottom right.

The given lengths of each arm are the length measured to the center of the coaxial cable as it passes through each notch. I made the notches by drilling a hole in the tubing and then cutting through the middle. If you want to make deeper notches, to hold the cable better, you'll want to make the overall length of the supports slightly longer than the dimensions given.

Although the support arms are hollow, the cable does not go through the support arms in order to pass through the mast. The purpose of the arms is simply to hold the cable in the correct shape. The electrical connections are all made at the top of the antenna, so the topmost support arm is placed right at the top of the mast. To make the connections, I secured a small square of copper perf board to the center of the topmost support arm, in the center of the hollow mast, and soldered the cables to it.

Where the cable passes through the lower section of the mast, I drilled two pairs of co-ax sized holes, one pair below the lowest short support, and one pair below the lowest long support. So the cable passes through the notches of the support, and then along the bottom of the support itself.

Each loop splits into two filars, which are supported by removable PVC arms B1, B2, S1 and S2. Figure 2 shows the connection of the filars in relation to each other. Note that the smaller loop is not connected at the bottom and for this reason filars S1 and S2 may be left joined so that a single length of co-axial cable 221.6 mmin length is used. The diagram shows connection details as viewed from the top of the mast, connections at the bottom and the joining of the feed cable.

NOTE here that S1 and S2 is just one cable with the ends soldered together. B1 and B2 are two coaxial cables soldered together at the top with one going through the 2" PVC tube to the bottom coaxial connector.

Critical distances are between the top and bottom offset posts. Middle one looks to be centered. No cutting / drilling until the templates are correct.

I lowered the gain set up on the RPi2 captures and noticed this morning that the wave file created was very noisy and I could hardly hear NOAA 19.

2" X 4" PVC measurements and cutting
1 - put the PVC tube adjacent to a 2 X 4 on a flat surface and drew a line end to end on it with a marker
2 - measured 4 feet from the end for first cut and used painting tape and a marker to mark it. (PVC tube purchased is 5 foot long)
3 - cut PVC tube to 4 feet using my old miterbox. (a table saw would also work)
4 - magic marked line about 3" from top of PVC. (so that cap fits).
5 - using the 1/2" pipe offset on the top such that I am using the center template on the top. The point to point measurements are from the higher offsets.
6 - templates show that from top to center we have a measurement of 346.18 mm which is 13.63 ".
7 - template shows from top to bottom measurements are 695.80mm which is 27.39"

Comment

Did an early morning (0630C) run to local big box store. Checked stock to see if they had 5-6 way PVC tees. They only had 5 way tee's via special order.

I went with my original list posted above.

Redid the drawing template using this site with correct dimensions printed to letter size.

Printed and tested size to fit 2" PVC pipe.

The antenna template is attached as a PDF file on this post.

Critical distances are between the top and bottom offset posts. Middle one looks to be centered. No cutting / drilling until the templates are correct.

I lowered the gain set up on the RPi2 captures and noticed this morning that the wave file created was very noisy and I could hardly hear NOAA 19.

Taking pictures and will do a composite picture with MS Visio.

2" X 4" PVC measurements and cutting
1 - put the PVC tube adjacent to a 2 X 4 on a flat surface and drew a line end to end on it with a marker
2 - measured 4 feet from the end for first cut and used painting tape and a marker to mark it. (PVC tube purchased is 5 foot long)
3 - cut PVC tube to 4 feet. Sanded rough edges and put caps on both sides of PVC pipe.
4- templates show that from top to center we have a measurement of 346.18 mm which is 13.63 ".
5- template shows from top to bottom measurements are 695.80mm which is 27.39"
6 - taped three offset templates on 2" pipe used line drawn earlier to align all three templates.
7 - used clear packing tape over templates.

9th of January, 2018 0900C

1 - Wiring up amplifier today. Amazon ~ $10.00. Fast delivery.

[ATTACH]65741[/ATTACH]

2 - soldered red and black lead and connected it to a 9VDC battery. Need SMA couplers which I do not have to connect amplifier.

[ATTACH]65746[/ATTACH]

3 - ordered some SMA stuff - couplers and SMA to F Type for antenna - way cheaper on Ebay than Amazon. Got the SMA stuff from Amazon cuz I wanted it fast.

4 - drilled holes today on the 2" PVC pipe. Freehand using a 7/8" drill bit. PITA. Templates helped a bunch. Started with a small pilot hole for each of the 12 holes.

[ATTACH]65748[/ATTACH]

5 -Got an OK good read today from NOAA19 using the small V dipole included in the kit. Note that this picture is from late in the afternoon around sunset central time.

Today will cut the the 1/2" PVC cross members. Will cut them a bit longer for notching for the coaxial cable. Relating the the coaxial cable loops from the top to the bottom there are two loops; one short and one long. The short loop starts at the top with two ends soldered together (center to center and braid to braid) and the two long loops are soldered at the top (separate braid to braid and center to center) and bottom. I am a bit confused as the author above describes one long loop going through the PVC to the bottom but the picture shows 4 wires (two loops) from the top 4 cross members to the bottom 4 cross members going in a counter clockwise path. IE: the left picture above shows B2 going through the 2" PVC tube where as the right picture shows B2 looping counter clockwise to the bottom.

Large loop is topmost of the three pairs of horizontal separators. Small loop is lower pair of the three horizontal separators. Note that I made all three staggered while the picture/template shows the top ones all equal.

Comment

Using only RG6 cable to built the quadrifilar helix (QFH). There are many ways to do this as documented above. You can do the same with 12/14 guage electrical wire. The RG6 is thicker and will hold it's shape better than 12 Gauge electrical wire.

I am not soldering, gluing at this time. I may drill some more holes.

My first test related to winding the RG6 cable from the bottom to the top of the antenna. First mistake was winding the loops clockwise which is incorrect. they have to be wired counter clockwise.

Short inner loop

The inner (small) loop can be made from a single length of co-ax, 221.6 cm (87.24") in length. Remove the insulation from each end of this length of cable, and connect the inner and outer together. Both ends will be connected at the top of the mast, one to the shield of the feeder, the other to the centre conductor.

Here threading the RG6 through the bottom 1/2" PVC, taping (later notching or drill a hole) through the center 1/2" PVC and threading the top RG6 through the 1/2" PVC. For the top PVC 1/2" tube will

1 - notch a hole in the center to thread the two RG6 ends and pull them out to the top. I have not measured the length of this one piece of RG6 cable.

2 - for center PVC axis will drill holes at the ends of the 1/2" PVC to thread the coaxial cable.

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12th of January, 2018 0800C

Long Outer loop

Half the outer (large) loop is made by cutting a length of coax 122.15 cm (48.09") i.e. half the total loop length) long, and joining the inner and outer at each end. At the top, this will be connected to the centre conductor of the feeder.

The second half of the outer loop is formed by the feeder cable itself. Strip away a small section of the outer jacket of the cable, 122.15cm from the end. The lower end of the other half of the loop is soldered to the braid. This is one of the trickiest parts of the whole construction: soldering to the braid of the feeder cable at this point without melting the inner insulator and causing a short circuit. After removing a section of insulator I tried pushing the two outer sections together, causing the braid to bunch up a bit. This ensured that when I soldered to the braid, it wasn't in contact with the inner insulator.

Rereading this it makes sense now to me. The length of the large loop cable is using a winding from top to bottom and the feeder RG6 from top to bottom making a sort of circle.

1 - solder each end of 1/2 of the large loop center lead and braid.
2 - top will be connected to center lead of the feeder
3 - feeder coaxial cable runs from the top to the bottom
4 - bottom of 1/2 of large loop will be connecting to the braid of the feeder (end) before exiting antenna.
5 - decided here to put the RG-6 end out the side of the bottom near the cap of the mast rather than the bottom cap.

Been reading too many folks do a 4-5 RG6 winding on the top of the antenna which is the feeder cable (this would be two more holes - in and out).
Going to notch large loop 1/2" PVC pipe for soldering the braid there to the feeder end braid and probably will drill out a 1/2" hole for the RG6 out.

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Though the feed for this antenna is technically 50 ohms impedance, it’s a balanced design. Fundamentally, coax is unbalanced. By coiling the cable around the mast a few times you’re able to implement a simple balun. I’m not sure how many times to do it, I’ve seen different numbers different places, so I chose 6; because, why not? It seems to work fine.

Personally decided to rewrite and draw (in Visio) the coaxial cable connectivity of the short and long loop. The only difference is the decription of the long loop and inclusion of the "feeder" RG6 cable. IE: At the top it uses the center of the coaxial feeder cable. At the bottom it uses the shielding of the long loop cable for the extra length. Note none of this has been validated to work yet. This is all related to the length of the elements versus the positioning of the elements and it gets confusing but it is one of two important pieces.

1 - shape of the elements - arrangement in the helix
2 - length of the short loop and long loop. (like two antennas built to one) Easy Peasey
A - short loop starts at the top, loops to the bottom (untouched) and goes back to the top feeder - using both shield and center of coax for length.
The short loop length is : 2278.3 mm = 89.6968504 inches = 7.474737533333 feet
B - long loop starts at the top and uses the shielding to extend the loop to the feeder at the bottom of the antenna)
The long loop length is: 2397.4 mm = 94.3858268 inches = 7.865485566667 feet
Different in the two loops is 4.6889764 inches.

Such that once tested will document each piece to be able to replicate it.

Comment

1 - updating drawings relating to making a Quadrifilar Helix (QFH) Antenna.
2 - playing with amplifier - added a ground to it.

14th of January, 2018 0800C

No improvements with amplifier here. Note that my antenna to SDR dongle to RPi are inches from each other.

Got no pictures.

The amplifier probably works better with longer antenna cable runs (like if an antenna is outside).

Did not ground the amplifier at this time. Removing it for time bean after 24 hours plus of no pictures.

Getting pictures now with clouds...

16th of January, 2018 0800C

Picture from earlier this morning.

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I am reading that the band across picture can be coming from RF noise from USB cable from RPi2 to SDR or a local transmitter (like an FM Radio station).

Back to working on Quadrifilar Helix (QFH) Antenna using PVC and RG6 cable. Reading on a search that the add of a balun on the top is not really going to do anything for me such that will just follow the template design of short and long loop RG6 wires. Guessing here making a mountain out of a mole hill in this endeavor such that will keep design simple. Long and Short loops will meet at the top and connect to one RG6 cable exiting the bottom of the antenna inside of the 2" PVC tub. Will not glue any of the PVC until tested with radio.

Comment

Basically all loops short and long end up at top - here will solder to one RG6 which will be terminated with RG6 F type connector at the bottom part of the PVC only coming out at the side of the tube. Long loops utilize longest runs of cable measured and longer 1/2" PVC cross tubes. Used the 1/2" notches on the two top PVC tubes for RG6.

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Today's pictures using the V-Dipole antenna in the attic.

[ATTACH]66004[/ATTACH]

Found my old SDR radio and noticed that one uses an MCX type of connector which I had configured with a BNC connector. That said purchased a bunch of SMA connectors and these are much easier to work with. My current CPE modem (backup WLAN and Phone is also using these)

18th of January, 2018 1600C

Got my SMA to F type couplers today. Going to do a test run without gluing anything to see what happens.
Shipping amplifier back and getting another one.

Pictures today.

[ATTACH]66032[/ATTACH]

19th of January, 2018 1600C

Todays plan is for redoing the RG6 feed wire with a balun on the top and a hole for exit on the bottom side rather than bottom of 2" PVC. Looked at a bunch of designs and noticed that most of them did have a balun on the top when using RG6 75 Ohm cable. (there is a difference between using 75 ohm and 50 ohm cable.) I probably should change the feed out a 50 ohm coaxial cable.

IE: the RG6 feed will start on the top of the 2" PVC, then exit a small hole near the top, and wrap around the 2" PVC 5 times then go back in to the 2" PVC and down and out of the side hole. The RG6 is not really that pliable so it is easy to feed. Then without gluing the PVC together will test run the antenna.

Comment

Finished Quadrifilar Helix (QFH) Antenna using PVC and RG6 cable. For the top terminations I soldered short pieces of color coded wires rather than soldering directly to the coaxial cable. It was easy as the short and long loops center/braids are soldered to one colored wire each. The feed coaxial cable used two wires - black and red.

No glue has been utilized at this time. The SDR is directly plugged in to the RG6 with a 15 foot or so with an active extender.

[ATTACH]66205[/ATTACH]

30th of January, 2018 1600C

No pictures in the last 24 hours. NOAA satellite signals are there but noise is as high as the signals.

Redoing antenna.

I originally put marks on the end of the RG6 for the short and long loops and they extended more than 8" from the top.
I will keep the RG6 feed and balun in place and will need to make the axis longer which is easy to do.

I do not understand that I did cut the lengths according to the formula. So each of the 6 1/2" pipes will be made 2-3" longer. The long and short loops are about 1" different right now and closer to 12". The above picture shows the cross section pipes to be closer to 14". Reading a bit one maker of the PVC said turning the antenna a bit counter clockwise or clockwise seems to improve the signal which I did not try. Ideally this would be done with the SDR radio program / gui listening and watching signal while moving antenna. Also I have been converting metric to inches and now changing to just measuring in metric as I did find one black and decker tape measure here (from about 5) that has both metric and inches on it.

Ordered a second SDR with antenna's today. Will configure radio software on laptop to play with radio / antenna on main floors rather than attic.

Comment

Readjusted the V-Dipole antenna. I am getting odd banding in the middle of the pictures. I should not have touched it. It is a PITA to adjust in the attic.

[ATTACH]66315[/ATTACH]

Waiting on the second SDR to test in the main part of the house out a window using the SDR program.

Will test the new antenna live before making adjustments to it in the kitchen (low on the WAF) using the radio program on the laptop.

This way I can test both the second V-Dipole antenna and the Quadrifilar Helix (QFH) Antenna.

Well too may connect the SDR to my Kodi box sitting to run the scripts just for testing. The KODI box is using an Aopen Ubuntu 16.04 64 bit set up.

3rd of February, 2018 1600C

1 - watched the following video:

2 - configured W7 laptop with SDR dongle and software for NOAA weather station listening. Note that Orbitron control SD radio software SDSharp. Note this is for a live view to test antennas in kitchen.

[ATTACH]66373[/ATTACH]

3 - Had a spare Shuttle Netop D525 and install Ubuntu 16.04 64 bit on it and the SDR software to capture NOAA images. This is moving my testing from the Kitchen table to 2nd floor office. Will also be installing software (Linux instead of Windows) as mentioned above.

Comment

1 - The installation of the same as above on Ubuntu 16.04 64 bit is a tad different as you are using the Intel versions of the software versus the 32 bit ARM versions of the software.

2 - wxtoimg software is a bit restricted running in freeware mode. Googled the issue and it appears that the software is no longer supported or sold. Found keys to update to professional mode and updated the RPi2 and the Ubuntu 16.04 64 bit machine (testing in office). I was able to update both computers to the professional version. For information on how to do this google wxtoimg updates.